Israel is ready to hold peace talks with Syria, the speaker of the US House of Representatives said today after meeting the Syrian president, Bashar Assad, in Damascus.

Nancy Pelosi's trip has angered the Bush administration, which accused the Democrats of sending mixed signals to Syria, listed by the US state department as a sponsor of terrorism.

Ms Pelosi told reporters that she had passed Israel's message on during her discussions with the Syrian leader.

"[Our] meeting with the president enabled us to communicate a message from prime minister [Ehud] Olmert that Israel was ready to engage in peace talks," she said.

Mr Olmert met Ms Pelosi at the weekend, asking her to pass on a message to Mr Assad that Israel was willing to talk to Syria if it openly took steps to stop supporting terrorism.

The visit to Damascus by Ms Pelosi has irritated the White House. Despite recommendations from the Iraq Study Group to start a dialogue with Syria and Iran, the Bush administration sees little point in such contacts until both countries change their behaviour.

"A lot of people have gone to see president Assad ... and yet we haven't seen action. He hasn't responded. Sending delegations doesn't work. It's simply been counterproductive," George Bush said yesterday.

Ms Pelosi defended her trip as an opportunity to rebuild lost confidence between Washington and Damascus and to tell Syrian leaders that Israel will only participate in peace talks if Syria stops supporting Palestinian militants.

The US accuses Syria of allowing Iraqi Sunni insurgents to operate from its territory, of backing the Hizbullah and Hamas militant groups and of trying to destabilise the Lebanese government. Syria denies the allegations.

Relations between the US and Syria hit a low point in early 2005, when Washington withdrew its ambassador to Damascus following the assassination of the former Lebanese prime minister, Rafik Hariri, which many Lebanese blame on Syria.

But Syria's isolation has eased recently with visits by US congressmen and some European officials.

The Syrian ambassador to Washington, Imad Moustapha, was quoted in the state-run press today as saying Syria was "wary of the sudden US openness" and would respond cautiously.

"Syria will not hurriedly offer concessions when it refused to offer them under much greater pressure from the United States in the past," he said.

Ms Pelosi's visit to Damascus is the latest sign of Democratic assertiveness in foreign policy, following votes in the House and the Senate setting out a timetable for the withdrawal of US troops from Iraq, in defiance of a veto threat from the White House.

The House speaker, the third highest ranked elected official in the US, behind the president and the vice-president, is the most senior American politician to visit Syria since relations between the countries went into deep freeze in 2003.

Earlier this week, Mr Olmert, proposed that Israel hold a regional conference with its neighbours to discuss a land-for-peace initiative drawn up by Arab leaders at a summit in the Saudi capital, Riyadh, last week.

The plan calls for a settlement including a Palestinian state in land occupied by Israel in 1967 and a "just solution" for the 4 million Palestinian refugees.

Mr Olmert at the time also took a conciliatory line with Syria, insisting his country had no plans to launch any military action against Damascus.